2. Blast Event within past 3 years during OIF/OEF deployment [event defined as any of the following symptoms or experiences occurring during or shortly after the blast or explosion: dazed, confused, saw stars, headache, dizziness, irritability, memory gap (not remembering injury or injury period), hearing loss, abdominal pain, shortness of breath, struck by debris, knocked over or down, knocked into or against something, helmet damaged, evacuated]